<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app">
        <h2>{{message}}</h2>
        <button @click="changeMessage">改变message</button>
    </div>
    <script src="./lib/Vue.js"></script>
    <script>
        const app = Vue.createApp({
            data() {//必须是函数
                return{
                    message:'Hello World'
                }
            },
            methods: {
                changeMessage(){
                    this.message = '你好，事件'
                }
            }
        })
        app.mount("#app")
    </script>
</body>
</html>